While visiting Scrub Brush, a frontier town, with their teacher, Edward "Egg" Garrison and his friends are told that someone is stealing the ticket money which could force the village to close and they set out to find the culprit.

While visiting the art museum with their teacher, Edward "Egg" Garrison and his friends realize that one of the paintings is a copy and try to investigate what happened to the original.

Catalina "Cat" Duran and her sixth-grade class are on a bowling trip, but in one lane the ball keeps going mysteriously off track, so the four friends decide to investigate the problem.

Samantha "Sam" Archer, her friends, and their "kindergarten buddies" are on a trip to the River City Children's Museum, which has been plagued by vandalism, and it is up to the sixth-graders and their new buddies to figure out who the vandals are and why they are set on closing the museum.

When the plans for the Bat-Wing, a historical aircraft, disappear from the Capitol City Air and Space Museum, eleven-year-old Amal Farah's father is blamed, and it is up to the four young friends to solve the mystery and save her father's job.

Sam, Egg, Gum and Cat, and the other members of the Franklin Middle School Science Club are on a guided tour of Greater River City Air Force Base (otherwise known as Zone 99), an aspiring science museum, and Gum is convinced that if they can sneak away from the group they will find evidence of aliens--and it is up to the reader to choose how their adventure unfolds.

A shipment of dinosaur bones meant for a new exhibit at the Capitol City Natural History Museum has disappeared, and so have the five paleontologists who were working late at the museum, including Wilson Kipper's mother--so Wilson and his museum friends set out to solve the mystery.

Somebody is vandalizing exhibits at the Capitol City Museum of American History, and it is up to twelve-year-old Raining Sam and his friends to find the culprit before irreparable damage is done.